A novel way to make stem-cell induction simpler has beeb introduced by scientists from Massachusetts Institute of Technology in Cambridge, and Harvard University.
Lead researchers Rudolf Jaenisch at the MIT and his former student Konrad Hochedlinger at Harvard University showed that adult mouse cells can now be reprogrammed to a stem-cell-like state with the help of a single genetic insertion - rather than the multiple gene insertions required in the past.
Three years ago, the research team made a breakthrough by creating the first induced pluripotent stem (iPS) cells, which can develop into any of the body's cell types.
But to induce pluripotency, four reprogramming genes known as Oct4, Sox2, Klf4 and c-Myc, had to be injected into the genome, which required multiple retroviruses, meaning the genes end up in random locations in the mouse genome, which can interfere with the function of the mouse's own genes.
In the new study, the research team has developed a technique that may ward off these difficulties.
They combined the four mouse reprogramming genes onto a piece of DNA, known as a cassette, and inserted it into a single locus in the mouse genome.
The mice were then bred, and their somatic cells were transformed into iPS cells following the addition of the antibiotic doxycycline, which triggers the cassette to express the four reprogramming genes.
"The advantage of this method is that the single gene has been introduced to a defined locus," Nature magazine quoted Hochedlinger as saying.
"The problem with a virus is that you never really know where it landed in the genome or how well it was expressed," Hochedlinger added.
The study appears in Nature Methods.